Create signatures for the transformation(input processing)/generation functions

[magicmatatjahu]

AC:

• create signatures for transformation (input processing) functions, it means for first step of data model generation flow
• create signatures for generation functions: generateModel, generateProperty etc.
• think how user can extend model (maybe second argument for generateModel will be good?)

Functions for transformation and generation can be splitted to the separated tasks

[asyncapi-bot]

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A few notes:

* We got this figured out :tada:
* We're going to use [this library](#link-to-website) to avoid losing time implementing this algorithm.
* We decided to go for the quickest solution and will improve it if we got time at the end of the cycle.

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:weight_lifting_woman: See the progress on the Shape Up Dashboard.

[magicmatatjahu]

/progress 75 Signatures for generation and transformation (input processing) are merged. We leave some time in next weeks (next tasks) to check if given signatures are friendly to developer, if no, we will slighty change them.

[magicmatatjahu]

/progress 90 Signatures are stable. If we change them in development process, we'll inform about that in this issue. Task will be opened until the end of the cycle.

[magicmatatjahu]

/progress 100 Signatures should be stable. Any further improvements/bugs will be added/fixed in the library as issues - https://github.com/asyncapi/generator-model-sdk/issues